使用Django开发简单接口实现文章增删改查
1、一些准备工作
安装django
pip install django
创建django项目
进入项目代码存放目录执行命令：
django-admin.py startproject blog_demo
进入blog_demo，运行命令：
python3.6 manage.py runserver 9000
在浏览器地址栏打开：http://127.0.0.1:9000/ 如果出现以下画面，则说明服务器正在运行
创建博客应用（app）
django中每一个app可以看作是一个模块，以app为单位，结构清晰，方便管理。
python3.6 manage.py startapp blog_api
使用开发工具打开项目blog_demo，其结构如下：
2、models.py
编写模型层代码，以下语句相当于创建了两张表：User，Article
class User(models.Model):
id = models.AutoField(primary_key=True)
uname = models.CharField(max_length=50)
upwd = models.CharField(max_length=100)
#active inactive
status = models.CharField(max_length=10)
class Article(models.Model):
id = models.AutoField(primary_key=True)
title = models.CharField(max_length=50)
content = models.TextField()
#deleted alive
status = models.CharField(max_length=10)
创建表结构：
python3.6 manage.py migrate
settings.py文件INSTALLED_APPS处新增app：blog_api
INSTALLED_APPS = [
'django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'blog_api'
]
让django知道模型有了变化：
python3.6 manage.py makemigrations blog_api
再次创建表结构：
python3.6 manage.py migrate
3、django admin
登录
在浏览器控制台输入：http://127.0.0.1:9000/admin/login/?next=/admin/
创建超级用户
stephen@stephen-K55VD:~/IdeaProjects/blog_demo$ python3.6 manage.py createsuperuser
Username (leave blank to use 'stephen'): admin
Email address:
Password:
Password (again):
This password is too common.
Bypass password validation and create user anyway? [y/N]: y
Superuser created successfully.
邮件地址可以不填，注册成功后即可登录。使用admin后台来管理模型需要先注册，修改blog_api/admin.py代码
#导入模型User,Article
from blog_api.models import User,Article
admin.site.register(User)
admin.site.register(Article)
刷新admin后台，就可以看到刚刚注册的模型了。
4、修改urls.py
from blog_api.views import add_article,modify_article
urlpatterns = [
path('admin/', admin.site.urls),
path('articles/',add_article),
path('articles/<int:art_id>',modify_article)
]
5、新增文章接口
from django.http import HttpResponse,JsonResponse
from blog_api.models import User,Article
import json
#新增文章
def add_article(request):
if request.method == "POST":
req = json.loads(request.body)
print (req)
key_flag = req.get("title") and req.get("content") and len(req)==2
#判断请求体是否正确
if key_flag:
title = req["title"]
content = req["content"]
#title返回的是一个list
title_exist = Article.objects.filter(title=title)
#判断是否存在同名title
if len(title_exist) != 0:
return JsonResponse({"status":"BS.400","msg":"title aleady exist,fail to publish."})
'''插入数据'''
add_art = Article(title=title,content=content,status="alive")
add_art.save()
return JsonResponse({"status":"BS.200","msg":"publish article sucess."})
else:
return JsonResponse({"status":"BS.400","message":"please check param."})
使用postman工具调用接口，运行结果：
6、查询文章接口
#查询所有文章和状态
if request.method == "GET":
articles = {}
query_art = Article.objects.all()
for title in query_art:
articles[title.title] = title.status
return JsonResponse({"status":"BS.200","all_titles":articles,"msg":"query articles sucess."})
运行结果：
7、修改文章接口
#修改文章
def modify_article(request,art_id):
if request.method == "POST":
req = json.loads(request.body)
try:
art = Article.objects.get(id=art_id)
key_flag = req.get("title") and req.get("content") and len(req)==2
if key_flag:
title = req["title"]
content = req["content"]
title_exist = Article.objects.filter(title=title)
if len(title_exist) > 1:
return JsonResponse({"status":"BS.400","msg":"title aleady exist."})
'''更新数据'''
old_art = Article.objects.get(id=art_id)
old_art.title = title
old_art.content = content
old_art.save()
return JsonResponse({"status":"BS.200","msg":"modify article sucess."})
except Article.DoesNotExist:
return JsonResponse({"status":"BS.300","msg":"article is not exists,fail to modify."})
运行结果：
8、删除文章接口
#删除文章
if request.method == "DELETE":
try:
art = Article.objects.get(id=art_id)
art_id = art.id
art.delete()
return JsonResponse({"status":"BS.200","msg":"delete article sucess."})
except Article.DoesNotExist:
return JsonResponse({"status":"BS.300","msg":"article is not exists,fail to delete."})
运行结果：
9、鉴权
四个简单的接口已经可以运行了，但是在发请求之前没有进行鉴权，毫无安全性可言。下面来实现简单的认证机制。需要用到内建模块hashlib，hashlib提供了常见的摘要算法，如MD5，SHA1等。
鉴权接口
新增一个专门用于鉴权的接口。在urls.py中添加
path("auth/",get_token)
在views.py前面新增函数get_token(request)
import hashlib
#获取token
def get_token(request):
req = json.loads(request.body)
uname = req["username"]
upwd = req["password"]
if request.method == "POST":
try:
tmppwd =User.objects.get(uname=uname).upwd
if upwd == tmppwd:
md5 = hashlib.md5()
#把密码变成一个长度固定的字符串
md5.update(upwd.encode("utf-8"))
return JsonResponse({"status":"BS.201","X-Token":md5.hexdigest()})
else:
return JsonResponse({"status":"BS.401","msg":"username or password may wrong."})
except User.DoesNotExist:
return JsonResponse({"status":"BS.500","msg":"username is not exist."})
登录django admin在blog_api下的User表新增一条记录。运行结果：
用户认证
request.META.get(“header key”) 用于获取header的信息。注意的是header key必须增加前缀HTTP，同时大写，中划先会转成下划线，例如你的key为X-Token，那么应该写成request.META.get("HTTP_X_TOKEN")，修改views.py在get_token后面加上如下代码：
#认证动作
def user_auth(request):
token = request.META.get("HTTP_X_TOKEN",b'')
print (token)
if token:
#暂时先写上auth接口返回的数据
if token=="0a6db4e59c7fff2b2b94a297e2e5632e":
return "auth_sucess"
else:
return "auth_fail"
else:
return "auth_fail"
在接口中调用user_auth函数，以发布文章接口为例：
#新增文章
def add_article(request):
auth_res = user_auth(request)
if auth_res == "auth_fail":
return JsonResponse({"status":"BS.401","msg":"user auth failed."})
else:
if request.method == "POST":
req = json.loads(request.body)
print (req)
.......
再次使用postman工具调用新增文章接口，Header中没有X-Token或X-Token错误时的运行结果：
